Most materials used for packaging are paper /card
based. Card and paper are made from wood pulp and waste paper. When
paper is examined through a microscope the fibres that form the material
can be seen. The fibres are made from cellulose which is extracted from
the wood pulp and recycled waste paper.

Wood pulp is the raw material and this comes from both coniferous and
deciduous trees. Other chemicals are added until the correct texture /
thickness is reached.

STAGES OF PAPER MANUFACTURE

A tree is cut down and
the trunk is fed into a chipping machine where it is cut into very
small pieces.

The wood chips are boiled in water to form a
thick wood pulp

Chemicals / ingredients
such as starch and bonding agents are added. The pulp is poured
over a fine mesh and the water escapes leaving the cellulose
fibres behind. This forms the paper.

Paper based materials such as cardboard are thick
because they are made up of several layers of pulp. If greater even
thickness is needed this is achieved by gluing layers of card together
in a process called laminating.

QUESTIONS:1. Describe as a series of stages,
the manufacture of paper.2. How is card manufactured?